Transition of deformation mechanisms from twinning to dislocation slip in nanograined pure cobalt. (10th September 2022)

• Record Type: Journal Article
• Authors: Qi, Y.W.; Luo, Z.P.; Li, X.Y.; Lu, K.
• Is Part Of: Journal of materials science & technology. Volume 121(2022)
• Page Start: 124
• Page End: 129
• Publication Date: 2022-09-10
• Subjects: Nanograin -- Cobalt -- Deformation mechanism -- Hall-Petch relation; Metals -- Periodicals; Materials science -- Periodicals; Materials science; Metals; Periodicals; 620.1105
• DOI: 10.1016/j.jmst.2022.02.009
• Languages: English
• ISSNs: 1005-0302

Abstract

Highlights: Gradient nanograined structures were prepared by plastic deformation in a pure cobalt sample. Atomic-scale observation for microstructure characteristics was conducted in nanograined cobalt. Comparing deformation mechanisms between nanograins and submicron-grains indicates a transition of governing deformation mechanism as reducing the gain size to nanoscale. Abstract: Deformation mechanisms of nanograined and submicron-grained pure cobalt processed by means of high strain rate shear deformation at cryogenic temperatures were studied. Microstructural analysis revealed a transition of governing deformation mechanism from deformation twinning and < a > dislocation slip in submicron-grains to < c + a > and < a > dislocations slip in nanograins. Microhardness tests illustrated that the Hall-Petch relation slope changes consequently with the transition of deformation mechanism. Graphical abstract: Image, graphical abstract